lock_guard two critical sections with one mutex
I have Get() and Set() methods and I want to make them thread safe. Wondering if I should use two mutex, one for Get and second one for Set or can I use one mutex, as in the code below.
public:
float Get(string name){
lock_guard<mutex> lock(mutex1);
return value_map[name];
}
Set(string name, float value){
lock_guard<mutex> lock(mutex1);
value_map[name] = value;
}
private:
map<string, float> value_map;
mutex mutex1;
multithreading c++11 dictionary thread-safety locking
asked Jan 3 at 1:36
RedFoxRedFox
336416
add a comment |
I have Get() and Set() methods and I want to make them thread safe. Wondering if I should use two mutex, one for Get and second one for Set or can I use one mutex, as in the code below.
public:
float Get(string name){
lock_guard<mutex> lock(mutex1);
return value_map[name];
}
Set(string name, float value){
lock_guard<mutex> lock(mutex1);
value_map[name] = value;
}
private:
map<string, float> value_map;
mutex mutex1;
multithreading c++11 dictionary thread-safety locking
asked Jan 3 at 1:36
RedFoxRedFox
336416
add a comment |
I have Get() and Set() methods and I want to make them thread safe. Wondering if I should use two mutex, one for Get and second one for Set or can I use one mutex, as in the code below.
public:
float Get(string name){
lock_guard<mutex> lock(mutex1);
return value_map[name];
}
Set(string name, float value){
lock_guard<mutex> lock(mutex1);
value_map[name] = value;
}
private:
map<string, float> value_map;
mutex mutex1;
multithreading c++11 dictionary thread-safety locking
asked Jan 3 at 1:36
RedFoxRedFox
336416
I have Get() and Set() methods and I want to make them thread safe. Wondering if I should use two mutex, one for Get and second one for Set or can I use one mutex, as in the code below.
public:
float Get(string name){
lock_guard<mutex> lock(mutex1);
return value_map[name];
}
Set(string name, float value){
lock_guard<mutex> lock(mutex1);
value_map[name] = value;
}
private:
map<string, float> value_map;
mutex mutex1;
multithreading c++11 dictionary thread-safety locking
multithreading c++11 dictionary thread-safety locking
asked Jan 3 at 1:36
RedFoxRedFox
336416
asked Jan 3 at 1:36
RedFoxRedFox
336416
asked Jan 3 at 1:36
RedFoxRedFox
336416
asked Jan 3 at 1:36
RedFoxRedFox
336416
asked Jan 3 at 1:36
RedFoxRedFox
336416
336416
add a comment |
add a comment |
1 Answer
1
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oldest
votes
You must use the same mutex for both. Two mutexes would be just as useless as no mutex at all - you'd still have a data race between Get and Set.
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
add a comment |
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1 Answer
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active
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votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You must use the same mutex for both. Two mutexes would be just as useless as no mutex at all - you'd still have a data race between Get and Set.
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
add a comment |
You must use the same mutex for both. Two mutexes would be just as useless as no mutex at all - you'd still have a data race between Get and Set.
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
add a comment |
You must use the same mutex for both. Two mutexes would be just as useless as no mutex at all - you'd still have a data race between Get and Set.
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
You must use the same mutex for both. Two mutexes would be just as useless as no mutex at all - you'd still have a data race between Get and Set.
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
answered Jan 3 at 2:08
Igor TandetnikIgor Tandetnik
32.8k33557
32.8k33557
add a comment |
add a comment |
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